The present invention relates to a new and improved method of setting or adjusting the adjustment of speed of the narrow sides or side walls of a plate mold during the continuous casting of metals, especially steel, wherein during the continuous casting operation there is increased the spacing between the narrow sides of the mold.
It is already known to the art to alter during the continuous casting operation the position of the mold walls of a plate mold, especially the narrow sides of the mold, and thus, to undertake a change in both the format or sectional shape of the cast strand or casting as well as an adjustment of the taper of the mold. In order to however make the length of the transition section or piece of the cast strand as short as possible--in other words the part of the strand between the initially cast sectional shape or format and the sectional shape which is to be newly cast--and to thus hold the losses in strand material to a minimum, it is necessary that the mold wall adjustment speed be selected as great as possible. But in so doing there exists the danger, particularly during adjustment of the mold walls towards the outside, that there will be formed at the strand bow-out and metal break-out phenomena.
It is also further known to positionally adjust the narrow sides of a plate mold, while changing their mutual spacing, at a speed of at most 2 millimeters per second in order to cast strands in the form of slabs. However, there is no teaching as to the manner and with what speed the adjustment is in fact to take place. Thus, it appears that disturbances, such as for instance metal break-out, also can arise within this indicated speed range.
Also there is known to the art a method of controlling the cooling capacity of the narrow side walls of plate molds during continuous casting as the same has been taught in Swiss Pat. No. 558,687. Here, before the start of casting the taper of the continuous casting mold is adjusted to a reference value which is accomodated to the contemplated casting speed and/or the casting temperature and during changes in the casting speed and/or the casting temperature during the casting operation there is adjusted the taper. To this end, the mold is provided with devices for measuring the cooling capacity or efficiency at the narrow side walls and with adjustment devices for the narrow sides of the mold.